HTTP/2 Based Push Notification In iOS

How To Implement HTTP/2 Based Push Notification In iOS?

December 06, 2022Posted By: ZealousWeb
HTTP/2 ProtocoliOS DevelopmentPush Notifications


Since its advent, iOS has remained a topic of widespread discussion. Developed by Apple Inc., iOS has consistently rivaled Android. A notable advancement in its latest version, iOS 9, is the introduction of HTTP/2-Based Provider API. This API, crucial for implementing Apple push notifications, leverages the HTTP/2 network protocol, enabling app developers to send remote notifications to their apps on iOS, tvOS, and OS X devices and to Apple Watch via iOS. Importantly, Apple announced that it will no longer support the legacy binary protocol after 31st March 2021. If you haven’t yet started using the HTTP/2-based APN provider API for your iOS push notifications, now is the time to transition. This blog aims to review the HTTP/2 API, elucidate how token-based authentication enhances the Apple push notification service, and provide a step-by-step guide to implementing HTTP/2-based push notifications in iOS projects.

Review Of The HTTP/2 API

HTTP/2, a binary protocol that underpins the iOS push notification system, is notably faster than traditional certificate-based communication. It facilitates multiple streams, allows instant feedback for inactive device tokens, and supports larger payloads of up to four kilobytes. Apple’s shift to HTTP/2 also reduces the overhead associated with certificate handling, streamlining the process of sending push notifications in iOS.

Token Authentication

Apple’s introduction of Token Authentication, a new method of authenticating with the Apple Push Notification Server (APNS), has revolutionized how push notifications are managed in iOS. This system, which replaces client certificates with provider tokens, simplifies the process of generating and renewing credentials. Numerous libraries are available in different programming languages to facilitate token generation, making it easier to manage push notification iOS systems.

How Token Authentication Works

Now, before getting into the details of how it works, let’s first recap how certificate authentication will work. You need to provide a client certificate from your developer account.

While connecting to APNS, your server sends this certificate while handshaking, and it validates the certificate and establishes a secure connection between your server and APNS. Any pushes you send on this connection are identified by the client certificate.

How Token Authentication Works

How Token Authentication Works


When using token authentication, you should opt-in to the token signing key from the developer account. Your server will then establish a connection without a client certificate. However, before sending notifications on this connection, your server will construct an authentication token that includes your team ID. Then, sign it using the private key. Now, it is possible to send notifications on this connection. Now, you have a clear idea about its terminology. Let me walk you through the steps to implement it.

Effortless Push: HTTP/2-Based Notifications In iOS Projects

To set up HTTP/2-based push notifications in iOS, you need the following:

  • Signing Key(P8 Certificate)
  • Private Key ID
  • Team ID
  • Bundle Identifier
  • Server

Let’s take a look at how to generate a signing Key. Login into your Apple developer account. Go to the certificates, identities, and profile section of the account.

Get Signing Key And Private Key ID

  • Go to the Keys section.
  • Click on create a key.
  • Provide a key name. Enable Apple Push Notification Service. Click continue.
  • Click Register.
  • You will get a Private Key ID. Also, click on download to get the p8 certificate.

Team ID

  • Go to the membership section and get your team ID.

Bundle Identifier

  • Go to the identifier section. Get your bundle ID from the list of IDs.


To effectively use the HTTP/2 protocol for Apple push notifications, ensure your environment is compatible. This includes .Net core 2.2 or higher, Windows Server 2016 or higher, Apache HTTP 2.4.17 or higher, or Nginx 1.9.5 or higher.

Send all these details to your backend team, and it will be used to generate a token. If you need a tool to test the push notifications, then this is a very handy tool that works with tokens and certificates. You can also test notifications on Android as well.

Here is the GitHub link:


We hope this guide on implementing HTTP/2-based push notifications in iOS has been informative. For further assistance or technical details on this subject, don’t hesitate to contact us. Embracing this technology in your iOS projects will streamline your processes, saving time and enhancing your development efforts. If you’re uncertain about the server-side implementation or seek more information, refer to our comprehensive tutorial for iOS app developers. For any further queries, feel free to get in touch; we’re here to assist in every way possible.


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